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A124992 Primes of the form 14k+1 generated recursively. Initial prime is 29. General term is a(n)=Min {p is prime; p divides (R^7 - 1)/(R - 1); Mod[p,7]=1}, where Q is the product of previous terms in the sequence and R = 7Q. 0
29, 70326806362093, 43, 127, 59221, 113, 32411, 71, 4957, 74509, 4271, 19013, 239, 2003, 463, 421, 613575503674084673, 32089, 211, 54601, 3109 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

All prime divisors of (R^7 - 1)/(R - 1) different from 7 are congruent to 1 modulo 14.

REFERENCES

M. Ram Murty, Problems in Analytic Number Theory, Springer-Verlag, NY, (2001), pp. 208-209.

LINKS

N. Hobson, Home page (listed in lieu of email address)

EXAMPLE

a(3) = 43 is the smallest prime divisor congruent to 1 mod 14

of (R^7 - 1)/(R - 1) =

8466454975669959912248567627122565866080343755024168315838344565727361366925647440393797835238961

= 43 * 10781 * 391441 * 428597443 * 11795628769 * 408944901028399 *

22566921596365593811470735460776534824496318810581339, where Q = 29 *

70326806362093 and R = 7Q.

CROSSREFS

Cf. A000945, A057204-A057208, A051308-A051335, A124984-A124993, A125037-A125045.

Sequence in context: A139775 A087528 A144839 * A023926 A022068 A198805

Adjacent sequences:  A124989 A124990 A124991 * A124993 A124994 A124995

KEYWORD

more,nonn

AUTHOR

Nick Hobson Nov 18 2006

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Last modified February 15 16:39 EST 2012. Contains 205823 sequences.